more from Frank Jackson

Single Idea 14288

[catalogued under 10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals]

Full Idea

According to Jackson, in asserting 'If A,B' the speaker expresses his belief that A⊃B, and also indicates that this belief is 'robust' with respect to the antecedent A - the speaker would not abandon A⊃B if he were to learn that A.


⊃ is the material conditional, so A⊃B means ¬AvB

Gist of Idea

'If A,B' affirms that A⊃B, and also that this wouldn't change if A were certain


report of Frank Jackson (On Assertion and Indicative Conditionals [1979]) by Dorothy Edgington - Conditionals (Stanf) 4.2

Book Reference

'Stanford Online Encyclopaedia of Philosophy', ed/tr. Stanford University [], p.22

A Reaction

The point is that you must not believe A⊃B solely on the dubious grounds of ¬A. This is 'to ensure an assertable conditional is fit for modus ponens' - that is, that you really will affirm B when you learn that A is true. Nice idea.

Related Idea

Idea 14289 There are some assertable conditionals one would reject if one learned the antecedent [Jackson, by Edgington]